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21.
Forty-eight healthy volunteers were administered a computerized battery of "ecological" memory tests simulating real life everyday tasks and actions such as recalling people's names or telephone numbers. The group was dichotomized according to recent criteria proposed by a NIMH study group. Younger individuals (below 50 years of age) always showed better performances than those over 50. Although the learning curves were significantly lower for the older subgroup, the forgetting rate did not differ, suggesting that most of the memory complaints of the elderly might be attributable to the initial encoding phase of the memorizing activity rather than to a retrieval problem. It seems that easy distractability and inefficient strategic elaboration of incoming information are also, at least in part, responsible for the memory problems associated with normal aging. This article reports preliminary findings of a normative and representative Italian population sample. 相似文献
22.
Targeted gene disruption of murine CD7 总被引:2,自引:0,他引:2
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig
superfamily. CD7 is a marker of mature human T cells and NK cells, and is
expressed early in their development. Cross-linking CD7 positively
modulates T cell and NK cell activity as measured by calcium fluxes,
expression of adhesion molecules, cytokine secretion and proliferation. CD7
associates directly with phosphoinositol 3'-kinase, and CD7 ligation
induces production of D-3 phosphoinositides and tyrosine phosphorylation.
Severe combined immunodeficiency has been associated with a lack of
lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog
is encoded by a single gene on chromosome 11. In order to characterize the
role of CD7 in lymphocyte development and function we have eliminated the
CD7 gene by targeted disruption. CD7- deficient mice display normal
histology of thymus and spleen, normal lymphocyte populations in primary
and secondary lymphoid tissues, and normal serum Ig levels. Specific
antibody responses after immunization with T-dependent and T-independent
antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient
lymphocytes respond normally to T cell mitogenic and allogeneic stimuli,
and display normal NK cell cytotoxicity.
相似文献
23.
Prof. Dr. C. -P. Sodomann G. Maerker-Alzer K. Havemann C. Dienst H. Schultz D. Mitrenga K. Schumacher G. A. Martini 《Journal of molecular medicine (Berlin, Germany)》1979,57(17):893-903
Summary It is a clinically and experimentally well supported working hypothesis that infection with hepatitis B virus may result in chronic active hepatitis in patients with suspected immune deficiencies. On this basis, a pilot study was performed in order to evaluate the effect of specific transfer factor (TF) in the treatment of HBs-Ag-positive chronic active hepatitis. From the leukocytes of 500 ml venous blood each of 40 volunteers that had completely recovered from acute virus hepatitis B within the last 6 months, a unique TF pool (40 units of TF) was prepared according to the method of Lawrence. Preexaminations indicated that this preparation was able to enhance cellular immune reactions in vitro. Thirteen patients with HBs-antigenemia and chronic active hepatitis (i.e., two liver biopsies within the last 6 or more months with the histological criteria of chronic aggressive hepatitis according to de Groote, elevated serum levels of bilirubin, alkaline phosphatase, transaminase activities, and/or -globulines) were randomized: Seven received s.c. injections of two units of TF each on days 1 and 15, the other six saline. Conversion of skin reactions to some ubiquitous antigens occurred in the TF group, but no significant and constant drop of HBs-Ag serum titers was observed. Although some of the biochemical parameters seemed to ameliorate in the TF group, the differences versus the control group did not prove to be significant within the limited number of patients under observation. The in vitro reactivity of patients' lymphocytes to HBs-Ag, tested by means of the3H-thymidine uptake, was never found enhanced after TF application. In the used doses, specific TF was not effective in the treatment of HBs-Ag-positive chronic active hepatitis; unfavorable side-effects were not observed. 相似文献
24.
Dr. F. Eberle C. Aßmus G. A. Martini 《Journal of molecular medicine (Berlin, Germany)》1979,57(10):499-509
Zusammenfassung 3 Generationen mit 37 Mitgliedern einer Familie mit multipler endokriner Adenomatose Typ I (MEA Typ I) wurden anamnestisch und katamnestisch erfaßt. Klinische, biochemische und histologische Befunde wurden zusammengestellt: 20 Personen hatten Erkrankungen oder Befunde, die für eine MEA Typ I charakteristisch sind.Ein Patient (II 1) hatte ein chromophobes Hypophysenadenom, Epithelkörperchen- und Inselzelladenome, eine knotige Kolloidstruma und eine bilaterale knotige Nebennierenrindenhyperplasie. Dies ist das voll ausgeprägte Bild einer MEA Typ I (Wermer-Syndrom). Außerdem hatte er ein medulläres Schilddrüsencarcinom.Bei 14 Familienangehörigen ergaben sich Hinweise auf primären Hyperparathyreoidismus (pHPT), darunter waren 5 Patienten mit Nierensteinen. Die bei 3 Personen exstirpierten Epithelkörperchen erlaubten eine histologische Bestätigung der Diagnose pHPT. Die nach Möglichkeit mehrmals durchgeführte Bestimmung des Calcium- und Phosphatspiegels im Serum spielte eine Hauptrolle bei der Entdeckung von asymptomatischen Trägern des Gens.6 Patienten hatten Magen-Darmulcera: darunter waren 5 Patienten mit sicherem oder wahrscheinlichem pHPT, von denen aber nur einer (II 1) ein Gastrinom und eine Inselzelladenomatose hatte. Drei Patienten hatten eine Pankreatitis, bei zwei von ihnen nachweislich kombiniert mit pHPT. — Zweimal fand sich eine euthyreote Struma, einmal eine hyperthyreote Struma. Zwei Familienangehörige hatten erhöhte Plasmacortisolwerte; Lipome im Unterhautfettgewebe hatten ebenfalls zwei Patienten. Der Befund eines Alpha-1-Antitrypsinmangels (ZZ Phänotyp) bei zumindest 2 Patienten mit pHPT läßt an eine genetisch bedingte Verknüpfung des Defektallels Z mit der MEA Typ I denken. Weitere Familienuntersuchungen sind für eine Beweisführung notwendig.Ein Polyp im Jejunum mit heterotoper Magenschleimhaut (Fundus- und Pylorusdrüsen) ausgekleidet und blutend wurde bei diesem Syndrome noch nicht beschrieben. Der Befund wird von uns als Entwicklungsstörung des Entoderm aufgefaßt. Das bei einem Patienten (II 1) gefundene medulläre Schilddrüsencarcinom zeigt, daß die Trennlinie zwischen MEA Typ I und MEA Typ II nicht immer scharf gezogen ist. 相似文献
25.
Baart EB Van Opstal D Los FJ Fauser BC Martini E 《Human reproduction (Oxford, England)》2004,19(3):685-693
BACKGROUND: Chromosomal mosaicism in human embryos may give rise to false positive or false negative results in preimplantation genetic diagnosis for aneuploidy screening (PGD-AS). Therefore, we have investigated whether the results obtained from a 2-cell biopsy of frozen-thawed embryos and fluorescence in situ hybridization (FISH) analysis are representative for the chromosome constitution of the remaining embryo on day 5. METHODS: Cryopreserved day 3 embryos were thawed and from surviving embryos two blastomeres were biopsied. FISH analysis was performed for chromosomes 1, 7, 13, 15, 16, 18, 21, 22, X and Y. After biopsy, the embryos were cultured until day 5 and further analysed using the same probe panels. RESULTS: In all, 17 embryos were available with a diagnosis based on two blastomeres on day 3 and confirmatory studies on day 5. In 10 of these 17 cases the initial diagnosis could be confirmed. However, in only six cases cytogenetic results were concordant. Besides the 10 cases with a 'correct' diagnosis, there were six false positive results and one false negative, all involving mosaicism. CONCLUSIONS: Investigating the chromosomal constitution of two blastomere nuclei offers a good opportunity to study the incidence of chromosomal mosaicism in early embryo development. The confirmation rate of the results obtained on day 3 depends on the interpretation and is higher when considered from a clinical than from a cytogenetic point of view. 相似文献
26.
Martini L Fini M Giavaresi G Torricelli P de Pretto M Rimondini L Giardino R 《Artificial cells, blood substitutes, and immobilization biotechnology》2003,31(4):449-466
Over the past decade extracorporeal shock-wave therapy (ESWT) has been increasingly applied to orthopaedic and musculoskeletal pathologies, the aim of this study was to assess how the energy density of the shock waves and the number of impulses affect viability, differentiation and synthetic activity of osteoblasts. Primary sheep osteoblasts cultures were treated with ESWT with an electro-hydraulic shock wave generator by selecting three different energy levels (14-21-28 kV corresponding at 0.15-0.31-0.40 mJ/mm2) and two different total numbers of impulses (500, 1000) for each level. At the end of treatment, cell counts and viability were recorded. Cells were then cultivated for 48 hours starting from a concentration of 1 x 10(4) cells/ml. The biological activity and viability were evaluated at 24 and 48 hours after treatment. No cytodestructive effects were observed in Group A, while a cytodestructive effect of ESWT was seen in cultures receiving the highest energy treatments. The different shock wave treatment induced differences in MTT assays after 24 and 48 hours, in particular the highest level showed a detrimental effect on cell respiration at both experimental times as compared to the Control Group and the protein metabolism was generally depressed by ESWT with impulses at the highest energy level. After 24 hours such effect further increased with the growing number of impulses. The lowest energy level appeared to significantly improve the metabolic parameter in primary cell cultures as compared to controls when 500 impulses were selected. The current study has demonstrated that one of the most important aspects to be considered is not the total number of impulses used but the energy level of the shock waves, thus confirming that ESWT has a dose-dependent effect on cells. 相似文献
27.
Muda M He C Martini PG Ferraro T Layfield S Taylor D Chevrier C Schweickhardt R Kelton C Ryan PL Bathgate RA 《Molecular human reproduction》2005,11(8):591-600
LGR7 and LGR8 are G protein-coupled receptors that belong to the leucine-rich repeat-containing G-protein coupled receptor (LGR) family, including the thyroid-stimulating hormone (TSH), LH and FSH receptors. LGR7 and LGR8 stimulate cAMP production upon binding of the cognate ligands, relaxin and insulin-like peptide 3 (INSL3), respectively. We cloned several novel splice variants of both LGR7 and LGR8 and analysed the function of four variants. LGR7.1 is a truncated receptor, including only the N-terminal region of the receptor and two leucine rich repeats. In contrast, LGR7.2, LGR7.10 and LGR 8.1 all contain an intact seven transmembrane domain and most of the extracellular region, lacking only one or two exons in the ectodomain. Our analysis demonstrates that although LGR7.10 and LGR8.1 are expressed at the cell surface, LGR7.2 is predominantly retained within cells and LGR7.1 is partially secreted. mRNA expression analysis revealed that several variants are co-expressed in various tissues. None of these variants were able to stimulate cAMP production following relaxin or INSL3 treatment. Unexpectedly, we did not detect any direct specific relaxin or INSL3 binding on any of the splice variants. The large number of receptor splice variants identified suggests an unforeseen complexity in the physiology of this novel hormone-receptor system. 相似文献
28.
Tognon M Martini F Iaccheri L Cultrera R Contini C 《Journal of medical microbiology》2001,50(2):165-172
Neurological diseases and a variety of neoplasms frequently occur in AIDS patients. Human JC and BK polyomaviruses have been associated with neurological disorders in such patients. SV40 polyomavirus sequences have been detected in human brain tumours, other neoplasms and normal tissues. JCV, BKV and SV40 DNA sequences were investigated in cerebrospinal fluid (CSF) samples from 12 AIDS patients affected by different neurological disorders, by PCR assay and filter hybridisation with specific internal oligoprobes, and DNA sequencing. Three of the 12 CSF samples were positive for JCV (one sample) or SV40 (one) DNA, or both (one). No sample was positive for BKV DNA. JCV- and SV40-specific genomic regions were confirmed by DNA sequencing. CSF samples from the two patients diagnosed clinically as having progressive multifocal leukoencephalopathy (PML) contained either JCV (one sample) or SV40 (one) DNA. The CSF found to contain both JCV and SV40 DNA originated from a patient with a cerebral mass lesion of unknown aetiology. These results suggest that SV40 may be involved in the aetiology of PML in AIDS patients, and raise the possibility that SV40 and JCV may act synergically in vivo to enhance their pathogenicity. 相似文献
29.
Pignatti P Ciapponi L Galle P Hansen MB Massa M Meazza C Paonessa G Novick D Ciliberto G Martini A De Benedetti F 《Clinical and experimental immunology》2003,131(2):355-363
We previously demonstrated that high levels of IL-6/sIL-6R complexes are present in sera of patients with systemic juvenile idiopathic arthritis (s-JIA) and that the amount of IL-6 estimated in the IL-6/sIL-6R complexes is markedly higher than that measured by the B9 assay. Here, we show that two additional bioassays, employing human myeloma XG-1 cells and human hepatoma Hep3B cells, detected serum IL-6 levels similar to those measured by the B9 assay and approximately 10-fold lower than the IL-6 levels estimated to be present in the IL-6/sIL-6R complex. Using an assay for the measurement of the amount of circulating IL-6 complexed with the sIL-6R and available for binding to gp130 (gp130 binding activity), we show that the IL-6/gp130 binding activity is similar to that detected by the bioassays and again significantly lower than that estimated to be present in the IL-6/sIL-6R complex. Addition of recombinant human IL-6 (rhIL-6) to sera of patients or controls results in a markedly lower increase in the gp130 binding activity in patients than in controls. Moreover, sera from s-JIA patients inhibited in a dose dependent manner the gp130 binding activity assay. These results show that sera from patients with s-JIA contain a factor, or factors, that inhibit(s) the binding of the IL-6/sIL-6R complex to gp130. This inhibitory activity does not appear to be due to soluble gp130, C-reactive protein or autoantibodies to IL-6. 相似文献
30.
H. Goebell H. Bickel Ch. Bode R. Egbring G. A. Martini 《Journal of molecular medicine (Berlin, Germany)》1968,46(10):526-533
Zusammenfassung 1. Die Aktivitäten von 28 Enzymen aus verschiedenen Abschnitten des Energiestoffwechsels wurden in isolierten Thrombocyten von 17 gesunden Menschen und 15 Patienten mit gesicherter Lebercirrhose gemessen.2. Die für Gewebe bekannte Proportionskonstanz der Enzymaktivitäten des zentralen Segmentes der Glykolyse (TIM, GAPDH, PGK, GPM und EN) findet sich auch in den Thrombocyten als Ordnungsprinzip. Die mitochondrial lokalisierten Enzyme NAD-spezifische Isocitratdehydrogenase und Glycerophosphatoxydase wurden erstmalig in Thrombocyten mit relativ hoher Aktivität nachgewiesen.3. Die Plättchen von Patienten mit Lebercirrhose und Milzvergrößerung infolge portaler Hypertension zeigten signifikant erhöhte Enzymaktivitäten in allen untersuchten Stoffwechselwegen, insbesondere der mitochondrial lokalisierten Enzyme. Funktionell bedeutsam erscheinen der ausgeprägte Anstieg der Mg++-aktivierbaren ATPase, die gleichbleibende Aktivität der Fructose-6-Phosphatkinase und eine Verminderung der Lactatdehydrogenase. Bei der Patientengruppe mit Cirrhose ohne Milzvergrößerung lagen fast alle gemessenen Aktivitäten der Thrombocyten im Normbereich.4. Es wird ein Patient mit Lebercirrhose ohne Milzvergrößerung beschrieben, dessen Thrombocyten um den Faktor 8 höhere Aktivitäten fast aller gemessenen Enzyme aufwiesen. Auch in diesen Plättchen zeigte die Lactatdehydrogenase eine Aktivitätsverminderung gegenüber der Norm.5. Ein Enzymdefekt der Plättchen wie bei Thrombasthenie wurde bei Lebercirrhose nicht gefunden. Nach unseren Kenntnissen über die Enzymausstattung von Blutzellen handelt es sich bei den Thrombocyten mit höherer Enzymaktivität um eine jugendliche Zellpopulation. Die Pathogenese wird besonders hinsichtlich der Rolle der vergrößerten Milz diskutiert.
Teilergebnisse wurden vorgetragen auf dem 2. Symposium der European Association for the Study of the Liver, Göteborg, 1967 und der 24. Tagung der Deutschen Gesellschaft für Verdauungs- und Stoffwechselkrankheiten, Hamburg 1967. 相似文献
Summary 1. The activities of 28 enzymes from different pathways of energy producing metabolism were measured in the isolated platelets of 17 normal persons and 15 patients with proven cirrhosis of the liver.2. In mammalian tissues a constant proportion between the enzymes of the central segment of the glycolytic pathway (TIM, GAPDH, PGK, GPM, EN) has been described. This constant proportion has been demonstrated also in the platelets. The mitochondrially localized enzymes NAD-specific Isocitratdehydrogenase and Glycerophosphatoxidase have been measured for the first time in platelets with a high activity.3. The platelets of patients with liver cirrhosis and splenomegaly following portal hypertension showed significant higher enzyme activities in all investigated pathways, mainly in the citric acid cycle. Functionally important could be the marked increase of the Mg++ activated ATPase, the unaltered activity of the Phosphofructokinase and a lowered activity of the Lactatdehydrogenase in these platelets. The patients with cirrhosis but without a large spleen had normal enzyme activities of the platelets.4. One patient is described with cirrhosis without splenomegaly who had an elevation of nearly all measured enzymes by a factor 8 in his platelets. The LDH showed a decreased activity.5. No enzyme defect in the platelets of cirrhotic patients as in thrombasthenia was found. Basing on our knowledge of the enzyme equipment of blood cells the conclusion is drawn that the platelets with higher enzyme content represent a young cell population. The pathogenesis is discussed with special reference to the role of the enlarged spleen.
Teilergebnisse wurden vorgetragen auf dem 2. Symposium der European Association for the Study of the Liver, Göteborg, 1967 und der 24. Tagung der Deutschen Gesellschaft für Verdauungs- und Stoffwechselkrankheiten, Hamburg 1967. 相似文献